Sounds great, man!
It’s hard to see your forearm in that video, but from I can see, your primary motion looks wrist based. Seems like pretty classic reverse dart thrower motion to me. You also adjust the pickslant for those little sweeps.
Giving technique recommendations for guys who play jazz is always tough. It really depends on the kind of sound you want. Jazz manouche players have a sound, and there’s a very specific way they play. Benson has a sound and a very specific way he plays. There are a handful of guys who pick every note (like Pat Martino) and that requires a double escape approach.
But from what you’re playing, it doesn’t sound like you’re going for any of those approaches. It sounds like you are going for, for lack of a better term, a post Metheny/Scofield sound. Lots of slurs, trying to emulate the phrasing of horn players. What most “modern” players are doing.
My only advice I give to players for that: on scalar lines, as much as you can, pick on the offbeats and slur into downbeats. I say “as much as you can” since, because of string switching, are pretty impractical to play at speed with this approach. It sounds like you’re already pretty much doing this, either consciously or not, which is what will happen if you transcribe horn players and really pay attention to the phrasing.
Because that approach uses so slurring so much, there are many ways to skin a cat (no pun intended). This isn’t bluegrass where strict alternate picking is a crucial part of the sound. If you look at Rosenwinkel, Kreisberg, Adam Rogers, Monder, etc, there’s a pretty wide range of motions that they use.
If you’re playing Sonny Stitt solos along to the records at tempo, I’d say whatever you’re doing is working right now. Is there an area that you feel like you’re struggling with? Otherwise, if it isn’t broke, don’t fix it.